One of the inspections required in nuclear power installations is the volumetric and wastage status of studs of reactor coolant pumps. The primary element carried down the bore of each of these studs is a transducer which must be moved along the length of the bore and rotated at predetermined positions in the translation.
The developed primary element is mounted on a shaft and the shaft is reciprocated the length of the stud bore and rotated. While mounted on the shaft, a transducer is electrically connected to manifesting equipment external to the bore to record the volume and wastage information of the stud. A high degree of precision is required to coordinate the physical location of the transducer within the bore to the signal received by the transducer and transmitted through its electrical connection to the manifesting structure. An encoder must be provided, as well as a connection between a motive means, which will translate the rotation of the motive means into linear movement of the primary element and its rotation. It has been the practice to manually control the shaft and transducer position within bores. The automation of transition and rotation is required to reduce the time of inspection and to provide a more accurate record.